Tedro S M, Meyer T E, Kamen M D
J Biol Chem. 1976 Jan 10;251(1):129-36.
The third amino acid sequence of a high potential iron-sulfur protein, that of the non-sulfur purple photosynthetic bacterium Rhodopseudomonas gelatinosa, has been determined. It consists of a single polypeptide chain of 74 amino acid residues, which is slightly smaller than the high potential iron-sulfur proteins from the sulfur purple bacteria Chromatium vinosum (85 residues) and Thiocapsa pfennigii (81 residues). The sequence of the gelatinosa protein is similar to the C. vinosum and T. pfennigii proteins with 38% and 37% identically matching residues, although six gaps are proposed for the comparison (the C. vinosum and T. pfennigii proteins have 44% identically matching residues out of 73 positions compared with only one 4-residue gap). Only 17 redisues, including the 4 cystein residues essential for binding the four-iron-sulfur chromophore, are invariant in the three known sequences. A discussion of the role of conserved residues in maintenance of the three-dimensional structure and in electron transport is presented.
已确定了一种高电位铁硫蛋白的第三条氨基酸序列，该蛋白来自非硫紫色光合细菌明胶红假单胞菌。它由一条含有74个氨基酸残基的单多肽链组成，这比来自硫紫色细菌荚膜红假单胞菌（85个残基）和芬氏硫囊菌（81个残基）的高电位铁硫蛋白略小。明胶红假单胞菌蛋白的序列与荚膜红假单胞菌和芬氏硫囊菌的蛋白相似，分别有38%和37%的残基完全匹配，不过在比对时提出了六个空位（荚膜红假单胞菌和芬氏硫囊菌的蛋白在73个位置中有44%的残基完全匹配，相比之下只有一个4残基的空位）。在这三个已知序列中，只有17个残基是不变的，包括结合四铁硫发色团所必需的4个半胱氨酸残基。文中对保守残基在维持三维结构和电子传递中的作用进行了讨论。
